| 1 | /** @file
|
|---|
| 2 | This file defines the macro setjmp, and declares the function longjmp
|
|---|
| 3 | and the type jmp_buf, for bypassing the normal function call and return discipline.
|
|---|
| 4 |
|
|---|
| 5 | Copyright (c) 2010 - 2011, Intel Corporation. All rights reserved.<BR>
|
|---|
| 6 | This program and the accompanying materials are licensed and made available under
|
|---|
| 7 | the terms and conditions of the BSD License that accompanies this distribution.
|
|---|
| 8 | The full text of the license may be found at
|
|---|
| 9 | http://opensource.org/licenses/bsd-license.
|
|---|
| 10 |
|
|---|
| 11 | THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
|
|---|
| 12 | WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
|
|---|
| 13 | **/
|
|---|
| 14 | #ifndef _SETJMP_H
|
|---|
| 15 | #define _SETJMP_H
|
|---|
| 16 | #include <Library/BaseLib.h>
|
|---|
| 17 | #include <sys/EfiCdefs.h>
|
|---|
| 18 |
|
|---|
| 19 | /** jmp_buf is an array type suitable for holding the information needed to
|
|---|
| 20 | restore a calling environment. The environment of a call to the setjmp
|
|---|
| 21 | macro consists of information sufficient for a call to the longjmp function
|
|---|
| 22 | to return execution to the correct block and invocation of that block, were
|
|---|
| 23 | it called recursively. It does not include the state of the floating-point
|
|---|
| 24 | status flags, of open files, or of any other component of the abstract
|
|---|
| 25 | machine.
|
|---|
| 26 | **/
|
|---|
| 27 | typedef BASE_LIBRARY_JUMP_BUFFER jmp_buf[1];
|
|---|
| 28 |
|
|---|
| 29 | /** The setjmp macro saves its calling environment in its jmp_buf argument for
|
|---|
| 30 | later use by the longjmp function.
|
|---|
| 31 |
|
|---|
| 32 | The Standard does not specify whether setjmp is a macro or an identifier
|
|---|
| 33 | declared with external linkage. If a macro definition is suppressed in
|
|---|
| 34 | order to access an actual function, or a program defines an external
|
|---|
| 35 | identifier with the name setjmp, the behavior is undefined by the Standard.
|
|---|
| 36 |
|
|---|
| 37 | @param[in,out] env A jmp_buf type object into which
|
|---|
| 38 | the current environment is stored.
|
|---|
| 39 |
|
|---|
| 40 | @return If the return is from a direct invocation, the setjmp macro
|
|---|
| 41 | returns the value zero. If the return is from a call to the longjmp
|
|---|
| 42 | function, the setjmp macro returns a nonzero value based upon the value
|
|---|
| 43 | of the second argument to the longjmp function.
|
|---|
| 44 | **/
|
|---|
| 45 | #define setjmp(env) (INTN)SetJump((env))
|
|---|
| 46 |
|
|---|
| 47 | /** The longjmp function restores the environment saved by the most recent
|
|---|
| 48 | invocation of the setjmp macro in the same invocation of the program with
|
|---|
| 49 | the corresponding jmp_buf argument. If there has been no such invocation,
|
|---|
| 50 | or if the function containing the invocation of the setjmp macro has
|
|---|
| 51 | terminated execution in the interim, or if the invocation of the setjmp
|
|---|
| 52 | macro was within the scope of an identifier with variably modified type and
|
|---|
| 53 | execution has left that scope in the interim, the behavior is undefined.
|
|---|
| 54 |
|
|---|
| 55 | @param[in] env The jump buffer containing the environment to be returned to.
|
|---|
| 56 | @param[in] val A non-zero value to be returned from setjmp.
|
|---|
| 57 |
|
|---|
| 58 | @return After longjmp is completed, program execution continues as if the
|
|---|
| 59 | corresponding invocation of the setjmp macro had just returned the value
|
|---|
| 60 | specified by val. The longjmp function cannot cause the setjmp macro to
|
|---|
| 61 | return the value 0; if val is 0, the setjmp macro returns the value 1.
|
|---|
| 62 | **/
|
|---|
| 63 | extern void longjmp(jmp_buf env, int val);
|
|---|
| 64 |
|
|---|
| 65 | #endif /* _SETJMP_H */
|
|---|
